Sensitive safety-lithoprint and process.



H. W. P. LORENZ. SENSITIVE SAFETY LITHOPBINT AND rnocnss. APPLICATIONFILED DBO. 21, 1909.

'967,794:. Patented Aug. 16, 1910.

Invader:

UNITED STATES PATENT OFFICE.

HENRY W. F. LORENZ, 0F JERSEY CITY, NEW JERSEY.-

SENSITIVE SAFETY-LITHOPRINT AND PROCESS. 4

Specification of Letters Patent. Patented Aug, 16, 1910.

Application filed December 21, 1909; Serial N 0. 534,388.

To all whom it may concern:

Be it known that I, HENRY W. F. Lonnnz, a citizen of the United States,and a resident of the city of Jersey City, in the county of Hudson andState of New Jersey, have invented a new and Improved SensitiveSafety-Lithoprint and Process, of which the following is. a clear, full,and exact description.

the past been made by using as the vehicle in the ink slow dryin oils inlace of the ordinarily employed drying oi s. The result has beenunsatisfactory. The oils envelop the sensitive color particles andprevent them, even in the most favorable cases, from being sensitive toany but bleaching solutions; eventually, when the oils have dried, allsensitiveness is lost. However, owing to the peculiarity-0f the lithoprinting process requiring an oily or greasy ink repellent to water, anoily or greasy vehicle for the litho ink cannot be dispensed with. Buttrue sensitive safety litho=prints must be free from greasy substances.

The object of my invention is a sensitive safety litho print devoid ofoil or grease,

- so as to be truly sensitive to the chemical reagents ordinarilyemployed in removing writing inkand having the sensitive colorifngmatter fixed firmly upon the paper sur ace.

In carrying out my invention I, ordinarily, may divide my processintofour steps, viz.: (1) preparation of the special ink, (2) printingtherewith from the ordinary litho stone, or from zinc, aluminium, etc,(3) steaming said print, and (4) removal of the vehicle from the ink onthe print (grease or oil varnish), and drying the print.

Reference is to be had to the accom anying drawings which form a part 0tthis specification.

Figure 1 represents a check, which is formed according to my invention,being printed with my special litho-ink. 1

Fig. 2 shows a sim le form of closed receptacle, or steaming 0x, intowhich steam sensitive lithoprints have in I enters at (C) and passes outat (B). (A

represents a removable glass door throng to steam vapor.

' Fig. 3 shows a simple formof dishcontaining a suitable solvent (E) inwhich is immersed the check This lattertreatwhich is seen the check (D)being subjected I I ment is for removing the vehicle from the ink on therint (grease or varnish). Subsequently t e print is returned, for drying(removing the solvent) to the steaming box as shown in Fig. 1, or driedin the air.

Whenever varnish is mentioned in this specification ap licant has inmind a litho varnish, prefera 1y one possessing non-drying properties,or very slow drying ones, for instance, such as can e made by blowingnonor slow-drying vegetable oils.

Examplesof slow drying oils are cotton seed oil, rape seed oil; veryslow drying or non-drying oils, castor oil, olive oil.

In preparing the special litho ink, I incorporate the chemicallysensitive coloring matter in a solution of a coagulable substance suchas, for instance, albumen, casein, gelatin or similar workingsubstances, coagulate these, by heat or chemically, and then thoroughlygrind the resultant mass in an ink mill with a large percentage of anon-drying oily or greasy varnish.

In place of the coagulable substances I may employ gelatinous bodiessuch as gelati'n,agar agar, gum trigura, tragacanth and the like,incorporating the sensitive coloring matters with these, permitting thesame to gelatinize by cooling, or otherwise, and then grinding theresultant mass, as described, with varnish.

The ink thus prepared is printed with in the ordinary way, from a stoneor from zinc or aluminium, the resultant print is preferably steamed(which steaming process should be carried out as soon as possible afterthe print has been made) and, finally, the print 1s washed with, orimmersed in, a suitable solvent for the oily ink vehicle and dried tofreeit from said solvent. The finished rint, freed from all oil orgrease, will be ound to be extremely sensitive to chemical reagents.Suitable solvents are, petroleum ether or gasolene, ordinary ether,benzene, carbon tetrachlorid, carbon bisulfid, etc.

A few examples will illustrate different modifications of my process.

The varnish employed must not be driable when the print is subjected tosteam vapor, otherwise the dried part of the vehicle could be extractedfrom the print only with difiiculty, if at all.

Another point to be noted is that the gelatinized, or coagulated masscontaining the coloring matter must not contain too much moisture, normust the same 'form too large a part of the litho ink. If this is thecase, the ink will not take properly on the stone, or metal, I havefound that the best working ratio of gelatinous or coagulated mass,

. containing'the coloring matter sensitive to added; Let the mass dryuniformly .until ture. and add four the moisture contenteqnals about 32per cent. Now take about one part of the above mixarts of varnish. Grindthoroughly in an ink mill and print with the resultant ink. Steam theprint and immediately immerse. it in petroleum ether. Let the print dry.Reactlons of the litho print: solutions'of oxalic acid, gray-black;

alkalies, redder; bleaching powder, bleached.

(2) Dissolve 4 parts of gelatin in 6- parts of water. Add 2 parts ofcotton red 4 B lake (C H N O b Ba). Now add enough formaldehyde to coaulate the mass.'

Permit the latter to dry uni rmly until the moisture content equalsabout 31 per cent. Now take-one part of the mixture and add five partsvarnlsh. Proceed as above mentioned., Reactionsv of litho print, same asi i ii' h 111 4 t f .3 1 est t roug y pars 0 egg albumen J..%Vlth 6 artsof water.- 'Add- 2 parts of cosmos red (Badische). Coagulate the mass byheating on a water bath." Let the coagulum dry uniformly until themoisture in the same equals-33 er cent. Now take onepart of the coagu umand add 6 parts "of varnish. Grind thoroughly in an 1nk.-mill and printwith the resultant ink. Steam the print and immerse it in ordinaryether. Let. the ether taken up by the paper evaporate. Reactions of thelitho solutions of oxalic acid, blue; .alkalies, redder; bleaching-po'wder,-bleached.

(4) Digest on a water bath l partzof agar agar with10 parts of water.Heat for some time.until a uniform mixtureis obtained, re lacing thewater that 'evapo-. rates b ad ingmore' water from time to time. t cooland permit the mass to elatinize; To prepare the litho ink procee' asfollows: takeof the agar agar jelly 10 parts and heat on a water bathuntil the vehicle in the finished print.)

print:

mass melts. Now add 2.5 parts of Congo red lake (0,,H,. .N,O,S. .Ba)containing about 10 er cent. of moisture, mixing thor oughly. let themass cool to gelatinize; then partially dr the same until the moisturecontent e ua s about 38 per cent. Now take a art 0 the above,semi-dried, mixture an' add five parts of varnish. Grind thoroughly inan ink mill and print with the resultant ink lit-hogra hically. -Steamthe print (steaming is not a ways necessary) and dissolve out thevarnish of the print with a solvent. oxalic acid, blue; alkalies, red,soluble; bleaching powder, bleached.

(5) Treat 5 parts of gum tragacanth with 40 parts of water. Digest on awater bath for at least 48 hours. 10 parts of Congo red are now added.Permit the mass'to dry until the moisture present equals about 25 percent. Take one part of the same and add "four parts of varnish. Grindthoroughly in an ink mill and rint with the resulting ink. Steam theprint made with this ink, ang dissolve out the vehicle as above descried. Finally, the print can be washed with water, the elatinous gum beingthus removed; the cclor being fixed on the paper.

Instead of proceeding as above described, I may also carry out myinvention of making a chemically sensitive litho print as follows: (Itwill be noted that in all cases I print with an ink containing an oilyor greasy vehicle and then get rid of this I may mix the chemicallysensitive coloring matter (or coloring matter previousl incorporatedwith a gelatinous or coagu able substance) witha volatile oily vehicle,print therewith Reactions: solutions of and subject-the resultant printto heat, or

steam vapor. or, I may employ a semivolat ile vehicle in which thenon-volatile part of the vehicle must be removed with a solvent, asabove described.

Examples are here appended ink with volatile wehz'ole.Take as thevehicle, for instance, 7 parts cedar wood oil and dissolve in it 5 partsof camphor. With this vehicle mix. thoroughly 2' parts of Congo redlake. Printwith this ink and subject the print to heat,-or steam vapor.

ink with semz'wolatile vehicle.Take as the vehicle, for instance, 7parts cedar wood oil and dissolve in it,5 parts of camphorfand 1 partof'varnishfor Venetian turpentine, then add 2 parts of Congo red. Printwith this ink, subject the print to steam vapor, and extract theresidual. part of the vehicle with a solvent. A It is evident thatin'the litho inks' mentioned in this specification inert bases, such asblanc fixe, sublimed lead, etc., may be present. A

but more direct processes for makin sensitive typographical prints areavailable. Washing out the gelatinous substance from finished print isnot strictly necessary.

I claim: I r

1. The process of making a sensitive safety litho print on paper forchecks, letters of credit, bank notes, postage and revenue and tradestamps, bonds, stock certificates and the like security papers, whichconsists in incorporating a chemlcally sensitive coloring matter inasolution of a 'coagulable substance, coa ulating said substance,thoroughly rin ing the coagulated mass in an excess 0 an oily vehiclesuch as varnish, printin-g lithographically on paper *ith the resultantink, steamin the prmt, and eliminating the oily vehicfia from the printby treatment with a solvent for the vehicle.

2. The process of making a sensitive litho print on paper for securitypapers, which consists in incorporating a chenncally sensitive coloringmatter in a solution ofa gelatinous substance, gelatinizing saidsubstance, thoroughly grinding the elatinous mass in an excess of anoily vehic e such as varnish, printing lithographically on paper withthe resultant ink, steaming the print, and elimi-- nating the oilyvehicle from the print by treatment with a solvent for said vehicle.

3. The process of making a sensitive litho safety prlnt on paper forsecurity papers, which consists in incorporating a chemically sensitivecoloring matterin a coagulable substance, coagulating said substance,thoroughly grinding. the coagulated mass in an oily vehicle suchas'varnish, printing therewith on paper, steaming the print, andeliminating the oily vehicle from the print by treatment with a solventfor said vehicle, and drying the print.

4. The process of making a sensitive safety litho print on paperforsecurity apers, which consists 1n incorporating a c emicallysensitive coloring matter in a gelatinous substance, coagulating saidsubstance, thoroughly grinding the gelatinous mass in ,an olly vehiclesuch as varnish, printing therewith on paper, steaming the print, andeliminating the oily vehicle from the print by treatment with a solventforsa'id vehicle, and drying the print.

The process of making a sensitive safety litho print on paper forsecurity apers, which consists in incorporating a c emically sensitivecoloring matter in an aqueous medium, thoroughly emulsifying this withan oily medium, printing therewith and eliminating the oily medium fromthe print.

6. The process of making a sensitive safety litho print on paper forsecurity papers, which consists in taking a chemically sensitivecoloring matter and incorporating it in a volatile vehicle, printingtherewith lithotherewith and eliminating both ra hicall on a er andsteamin the rint is o di'ive 0% said r olatile vehicle a nd fii: thecoloring matter on the pape 7. The process of making a sensitive safetylitho print on paper for security papers, which consists in taking achemically sensitive coloring matter and incorporating it in- I fixed onthe paper surface.

9. The process of making a sensitive safety print lithographically onpaper for security papers, which consists in taking a water-' solublemedium containing a chemically sensitive coloring matter and emulsifyingit thorou hly with an oily medium, printing therewith and elimina ingthe oily medium from the print.

10. The process of making a sensitive safety litho print on paper forsecurity papers, whichconsists 1n incorporating a chemically sensitivecolorin matter in a gelatlnous substance, gelatimzing said substance,thoroughly grlnding the gelatinous -mass in varnish, printing therewithon paper, and eliminating the oily vehicle from the print by treatmentwith a solvent for said vehicle, and drying the print.

-11. As a new article ofmanufacture, a chemically sensitive safety lithoprint devoid of vehicle.

12. A chemically sensitive safety litho print from which the oily andreasy vehicle has been removed by evaporation.

13. A chemically sensitive safety litho print from which the oily andgreasy vehicle has been removed by asolvent.

14. A chemicall sensitive safety litho print having the chemicallysensitive color, incorporated in a gelatinous mass, residually upon thepaper.

15. A chemically sensitive safety litho print having the chemicallysensitive color and gelatinous mass left residually upon the papersurface.

16. A chemically sensitive safety print on paper, made lithographically,having the sensitive color firmly attached to the paper surface.-

17. The process of making a sensitive safety litho print on paper forsecurity papers, which consists in incorporating a chemicallysensitive'coloring matter in an aqueous gelatinous medium, thoroughlymixing this, with an oily medium, printing aqueous apers,

18. The process of making a sensitive safety lit-ho print on. paper forsecurity papers, which consists 1n incorporating a chemically sensitivecoloring matterin an aqueous gelatinous medium, thoroughly mixprinting eing this with an oily medium,

therewith,- steaming the print, and lminating the oily medium andaqueous gelatinous -medium, leaving the coloring matter fixed upon thepaper surface.

In witness whereof I have subscribed my name to this specification inthe presence of 15 two subscribing witnesses.

HENRY W. F. LORENZ.

Witnesses:

CHARLES MILLER, FRANK HACKETT.

